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%I #10 Aug 17 2023 08:16:42
%S 1,1,14,947,161388,56558003,36757837732
%N a(n) is the maximal permanent of an n X n matrix using the integers 1 to n^2.
%e a(2) = 14:
%e [2, 3;
%e 4, 1]
%e .
%e a(3) = 947:
%e [3, 7, 6;
%e 9, 4, 1;
%e 2, 5, 8]
%e .
%e a(4) = 161388:
%e [ 2, 3, 16, 6;
%e 11, 13, 4, 10;
%e 8, 9, 5, 15;
%e 14, 12, 1, 7]
%e .
%e a(5) = 56558003:
%e [10, 2, 19, 25, 3;
%e 11, 5, 23, 20, 8;
%e 21, 14, 12, 9, 15;
%e 13, 24, 6, 1, 18;
%e 16, 17, 7, 4, 22]
%e .
%e a(6) = 36757837732:
%e [32, 30, 3, 19, 23, 2;
%e 1, 5, 34, 14, 11, 36;
%e 17, 18, 15, 31, 22, 16;
%e 29, 28, 7, 20, 24, 6;
%e 26, 25, 10, 21, 27, 9;
%e 4, 8, 35, 13, 12, 33]
%o (Python)
%o from itertools import permutations
%o from sympy import Matrix
%o def A350566(n): return 1 if n == 0 else max(Matrix(n,n,p).per() for p in permutations(range(1,n**2+1))) # _Chai Wah Wu_, Jan 21 2022
%Y Cf. A085000, A350565, A350858, A350859.
%K nonn,hard,more
%O 0,3
%A _Hugo Pfoertner_ at the suggestion of _Stefano Spezia_, Jan 21 2022